Air pollution is a recognized risk factor for cardiovascular disease, and new research indicates that it is especially detrimental for women with type 2 diabetes. Investigators at Brigham and Women’s Hospital in Boston and the Harvard T.H. Chan School of Public Health reviewed data from more than 100,000 women, comparing rates of cardiovascular disease in connection with air pollution. They found that among women who were affected by air pollution, type 2 diabetes was a more important factor than age, family history of cardiovascular disease, a woman’s weight, smoking, and region of the country. For non-diabetics in the study, long-term exposure to air pollution led to small, but statistically insignificant increases in the risk of cardiovascular events. The researchers reported that for each increase of 10 micrograms per cubic meter of air pollution, a woman’s risk of cardiovascular disease rose by 44 percent if she had type 2 diabetes. The 10 micrograms increase in pollution is the equivalent of the difference in air quality between Los Angeles and St. Louis. The researchers suggested that women at higher risk of cardiovascular disease, and especially those with type 2 diabetes, take precautions to limit their exposure to air pollution. They also suggested following recommendations to lower the risk of cardiovascular disease by not smoking, eating a healthy diet and getting regular exercise.

If you often sleep in on weekends, you may be increasing your risk of heart disease and diabetes. In fact, a study from the University of Pittsburgh suggests that the greaterthe difference between the time you usually get up on weekdays and how late you sleep on weekends the greater the risk. Researchers tracked 447 men and women ages 30 to 54 and determined that those who slept later on weekends had lower HDL (“good”) cholesterol, higher triglycerides, higher insulin resistance and higher body mass index than those who kept consistent sleep schedules throughout the week. The link between sleeping habits and these factors remained even after the researchers controlled for physical activity, caloric intake, drinking alcohol, and symptoms of depression. During the 7-day study the participants wore devices that recorded when they fell asleep and woke up, and also measured their movements night and day. Almost 85 percent of the participants woke later on days when they didn’t have to go to work. Earlier research revealed an association between shift work and an increased risk of heart disease and diabetes. It’s not yet known whether the effects seen in the study from sleeping in on weekends are long lasting.

Drinking 1.5 cups or more of coffee daily seems to lower the risk of developing type 2 diabetes according to newly published research from Greece. This isn’t the first study to link coffee consumption to a reduced risk of diabetes, and its findings don’t add up to proof that coffee really was responsible for the lower risk seen. But the researchers at Harokopio University in Athens reported that higher coffee consumption was associated with lower levels of an inflammatory marker called serum amyloid, an observation thatmight explain the link between coffee and diabetes. More than 1,400 men and women age 18 and older were selected for the study in 2001 and 2002. Of this group 816 were deemed “casual” coffee drinkers who consumed less than 1.5 cups per day while 385 participants were “habitual” coffee drinkers who consumed 1.5 cups or more daily. The remaining 239 participants didn’t drink coffee at all. When the study ended 10 years later, 191 men and women in the study group had developed diabetes; the risk among habitual coffee drinkers was 54 percent lower than that of the other groups in the study even after the researchers accounted for such factors as smoking, high blood pressure, family history of diabetes and intake of other caffeinated beverages.

My take: A number of studies have linked habitual coffee consumption to lower rates of type 2 diabetes. One from University of California, Los Angeles, published in 2011 shed new light onwhycoffee may be protective. The investigators focused on a protein called sex hormone-binding globulin (SHBG), which regulates the activity of testosterone and estrogen, hormones believed to play a role in the development of the disease. The researchers determined that coffee boosts blood levels of SHBG and found that women who drank at least four cups daily had less than half the risk of developing type 2 diabetes compared to women who didn't drink any coffee.

Bear in mind that lifestyle has a primary influence on the well established risk factors for this disease, which includes being overweight and sedentary. If you have these or other risk factors for type 2 diabetes, don't rely on coffee to protect you.

Exposure to pesticides may increase the risk of developing type 2 diabetes by 64 percent, according to a new analysis of 21 studies by researchers in Greece and England. Another investigation reported that women who had elevated blood levels of polychlorinated biphenyls (PCBs) during the first trimester of pregnancy were more than four times more likely than normal to develop gestational diabetes. While the researcherswho conducted the analysis said that their results don’t prove that pesticides cause some cases of diabetes, they maintained that the findings add to a growing body of evidence suggesting that environmental contaminants play a key role in the development of the disease. After reviewing the studies, which included data on nearly 67,000 people, the researchers concluded that the increased risks seen were associated with the organic pollutants DDT, dieldrin, heptachlor, and HCB. Most of the studies included in the review identified pesticide exposure via urine and blood analyses, methods that are considered very accurate. The authors of bothanalyses said that while diet, weight and exercise factors are also key to diabetes’ risk, the role of chemicals cannot be ignored. Animal and laboratory studies have shown that endocrine-disrupting chemicals can provoke precursors to diabetes and even diabetes itself. Results of both new analyses were presented at the September 2015 meeting of the European Association for the Study of Diabetes.

Last blog post covered five foods for healthy blood sugar levels, including okra and onions. Today we look at five more - add these foods to your diet, as they may help lower blood sugar levels.

Maitake mushrooms. One of Dr. Weil's favorites, maitake not only contain compounds that enhance immune function, but appear to lower blood sugar levels as well. Cook some up and serve as a side dish!

Underground vegetables. Also known as tubers, veggies such as leeks, potatoes and yams have been shown in studies to lower or return to normal high blood sugar levels.

Brewer's yeast. Rich in essential amino acids and B vitamins, brewer's yeast may also lower blood sugar in people with type 2 diabetes, and may improve glucose tolerance, increase insulin sensitivity, and lower cholesterol as well. Shake some on your next batch of popped corn!

Prickly pear. The green pads of this plant are called nopal, a staple of Mexican cuisine that is very low on the glycemic index and may have blood-sugar-lowering effects. Look for it at specialty or ethnic grocers.

Bitter melon. When cooked and added to other dishes, bitter melon will impart a unique flavor that may help glucose tolerance in people with type 2 diabetes, and help keep blood sugar levels in the normal range.

Eating yogurt regularly may lower the risk of type 2 diabetes. Researchers from the Harvard School of Public Health followed nearly 200,000 adults ages 25 to 75 for up to 30 years, checking in on them regularly through food questionnaires. After adjusting for age, smoking, body mass index and other risk factors, the team concluded that consuming 12 ounces of yogurt daily - three times the usual four-ounce serving - was linked to an 18 percent reduction in the risk for Type 2 diabetes. The study also found that consumption of other dairy products didn't seem to make a difference to the risk of diabetes. Lead author Mu Chen told the New York Times that yogurt's positive effect might be due to the probiotic bacteria it contains, although that remains to be studied. Frank Hu, the study's senior author, was quoted in news reports as saying that the benefits may stem from yogurt's high protein content, which can increase satiety and reduce feelings of hunger, or it could be that regular yogurt consumption is simply a marker for a healthy lifestyle.

Maybe so, and worse, it could lead to heart disease. A new study of seniors living in Massachusetts suggests that black carbon, a component of traffic-generated air pollution, influences levels of leptin. High levels of this hormone are associated with obesity, diabetes and heart disease.

A team of researchers from Brown University measured blood levels of leptin in 765 seniors living in Boston and found that levels of the hormone were 27 percent higher among those with the most exposure to black carbon. These individuals also had lower incomes and higher rates of high blood pressure and diabetes than others in the study. The research team didn't establish where the pollution was generated, reporting that the proximity of the nearest major highway was not apparently related to leptin levels. Rather, they suggested that black carbon exposure probably reflects overall pollution from traffic on a wider range of roads in the immediate vicinity of the participants' homes. The study doesn't prove that black carbon exposure increases leptin levels, but the researchers suggested that their findings may help explain increases in cardiovascular disease associated with air pollution.

We know that the excessive amount of sugar in western diets isn't healthy, and now a study from the U.K. has identified sugar as the onlycause of tooth decay in children and adults. That finding implicates all the sugars in our diets, especially those added to food (including beverages) by manufacturers, as well as the sugars found naturally in honey, syrups, fruit juices and fruit concentrates. The researchers backed up their findings with epidemiology linking sugar consumption with tooth decay across the globe. For instance, during World War II, tooth decay was "hugely reduced" in Japan, but increased after the war when sugar could again be imported. The researchers also reported that only two percent of the people in Nigeria (whose diets contain negligible amounts of sugar) have tooth decay, compared to 92 percent of adults living in the United States. To rein in this problem, the researchers from University College London and the London School of Hygiene & Tropical Medicine recommended reducing the amount of sugar in the diet to less than three percent of total calories (that would work out to 60 calories on a 2000 calorie daily diet). Current guidelines from the World Health Organization set a maximum of 10 percent of total calories from sugar with a target of half that amount, five percent.

My take? In addition to its unwelcome effect on teeth, sugar has a negative impact on health in general. Diets high in sugar may predispose some people, especially women, to yeast infections, may aggravate some kinds of arthritis and asthma and may raise triglyceride levels. In people genetically programmed to develop insulin resistance, high-sugar diets may drive obesity and high blood pressure and increase risks of developing type 2 diabetes. Our physiology does not require foods made with copious amounts of sugar, and does not respond well to it. Cutting sugar back to three percent of total calories is a tough goal, but it would have a considerable positive payoff for your teeth - and the rest of your body.

A low carbohydrate diet might not pare more pounds than a low fat diet, but Swedish researchers found that it works better to lower inflammation in individuals with type 2 diabetes. Over the two-years of a clinical trial with 61 type 2 diabetes patients, investigators at Sweden’s Linköping University found reduced levels of inflammatory markers only in those who followed a low carb diet. When the trial began, the patients were randomly assigned to either a low carb or a traditional low fat diet and were given menu suggestions and advice by a dietician. At the outset of the investigation, levels of inflammation in the diabetes patients were found to be significantly higher than those of healthy individuals without diabetes. However, after six months, inflammation was significantly reduced among the patients on the low carb diet; no changes were seen in the patients who had followed the low fat diet. Both groups lost about the same amount of weight, 4 kilograms (about 8.8 pounds). Inflammation is believed to be a primary contributor to the higher risks of heart disease and other complications seen in patients with type 2 diabetes.

We continue our look at foods that can help keep your blood sugar levels optimized with five more to add to your diet. Find out what to put on your next grocery list!

Tuesday's post covered five foods for healthy blood sugar levels, from green leafy veggies to onions. Today we look at five more - add these foods to your diet, as they may help lower blood sugar levels.

Maitake mushrooms. One of Dr. Weil’s favorites, maitake not only contain compounds that enhance immune function, but in one study people with type 2 diabetes were given maitake along with diabetes medication, and the result was lower blood sugar readings. Cook some up and serve them as a side dish!

Underground vegetables. Also known as “tubers,” veggies such as leeks, potatoes and yams have been shown in studies to lower or return to normal high blood sugar levels.

Brewer’s yeast. Rich in essential amino acids and B vitamins, brewer’s yeast may also lower blood sugar in people with type 2 diabetes, and may improve glucose tolerance, increase insulin sensitivity, and lower cholesterol as well. Shake some on your next batch of popped corn!

Prickly pear. The green pads of this plant are called nopal, and is more than a staple in Mexican cuisine – it is very low on the glycemic index and may have blood-sugar-lowering effects. Look for it at specialty or ethnic grocers.

Bitter melon. When cooked and added to other dishes, bitter melon will impart a unique flavor that may help glucose tolerance of people with type 2 diabetes, and help keep blood sugar levels in the normal range.